IGMP Snooping (multicast forwarding) on AX routers?

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Smallnetbuilderguy

New Around Here
I have the GT-AC5300 and am shocked that it doesn't have IGMP Snooping to support my new IPTV service at home, because I thought this router has everything. So here are my questiosn:

1. Does anyone know or can anyone with GT-AX11000 check if Enable efficient multicast forwarding (IGMP Snooping) feature is available under LAN - IPTV?

2. Will the new AX89X have IGMP Snooping?

3. Surprisingly, older routers like RT-AC66u, RT-AC87U do have IGMP Snooping based on demoui links listed on this post but I don't really want to go back to older routers. So the RT-AC5300 is a smaller step-down from my GT-AC5300 but I can't confirm if RT-AC5300 has IGMP Snooping either. This page does show this function available but I suspect it is a screenshot of an old firmware. Can someone check/confirm this? I can't find a demoui link to check this myself.

5. Why does a newer router like RT-AX88U not have IGMP Snooping either? I would have considered this router too but demoui shows IGMP Snooping function missing.
 

RMerlin

Asuswrt-Merlin dev
The GT-AC5300 has a different multicast daemon to handle IGMP snooping/proxying, called mcpd. It's automatically configured when the WAN connects. Its config file can be seen in /var/mcpd.conf:

Code:
[email protected]:/tmp/home/root# more /var/mcpd.conf
##### IGMP configuration #####
igmp-default-version 3
igmp-query-interval 20
igmp-query-response-interval 100
igmp-last-member-query-interval 10
igmp-robustness-value 2
igmp-max-groups 25
igmp-max-sources 25
igmp-max-members 25
igmp-fast-leave 1
igmp-admission-required 0
igmp-admission-bridging-filter 0
igmp-proxy-interfaces eth0
igmp-snooping-interfaces br0
igmp-mcast-interfaces eth0

##### MCAST configuration #####
igmp-mcast-snoop-exceptions 239.255.255.250/255.255.255.255 224.0.255.135/255.255.255.255
mld-mcast-snoop-exceptions ff05::0001:0003/ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff
 

organshifter

Regular Contributor
I have the GT-AC5300 and am shocked that it doesn't have IGMP Snooping to support my new IPTV service at home, because I thought this router has everything. So here are my questiosn:

1. Does anyone know or can anyone with GT-AX11000 check if Enable efficient multicast forwarding (IGMP Snooping) feature is available under LAN - IPTV?

2. Will the new AX89X have IGMP Snooping?

3. Surprisingly, older routers like RT-AC66u, RT-AC87U do have IGMP Snooping based on demoui links listed on this post but I don't really want to go back to older routers. So the RT-AC5300 is a smaller step-down from my GT-AC5300 but I can't confirm if RT-AC5300 has IGMP Snooping either. This page does show this function available but I suspect it is a screenshot of an old firmware. Can someone check/confirm this? I can't find a demoui link to check this myself.

5. Why does a newer router like RT-AX88U not have IGMP Snooping either? I would have considered this router too but demoui shows IGMP Snooping function missing.

 

RMerlin

Asuswrt-Merlin dev
@RMerlin I don't have enough skills to go into config file, just to make sure I understand correctly, you are saying that IGMP Snooping is "enabled" by default?

That's correct. Both proxying and snooping.
 

Smallnetbuilderguy

New Around Here
Thanks @RMerlin for confirming existence of IGMP proxying and snooping on GT-AC5300.

Now I wonder what other possible reason could it be that my Telus IPTV box connected to GT-AC5300 is experiencing the same issue (ie. interruption/stop of IPTV stream after 10-15 seconds) that others are experiencing when IGMP protocols are not working properly?

Could it be that Asus routers just simply don't have the advanced IGMP configurations required, like the ones available on the default Telus IPTV Actiontech T3200M router, shown in this screenshot?
 

Attachments

  • Screen Shot 2019-08-29 at 11.56.09 AM.png
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ColinTaylor

Part of the Furniture
Could it be that Asus routers just simply don't have the advanced IGMP configurations required, like the ones available on the default Telus IPTV Actiontech T3200M router, shown in this screenshot?
It looks like all those options are adjustable via custom config files on the Asus as well according to his post #2.
 

Smallnetbuilderguy

New Around Here
@ColinTaylor thanks for noticing that, I am now faced with the following questions:

1. How do I browse/get to the config file?

2. Does "merlin" firmware allow easier access?

3. Is my GT-AC5300 one of those newer routers without custom firmwares?

4. Are all new Asus AX routers not compatible with custom firmwares (in case I want to upgrade to AX router in future?

5. Does anyone know of any guides on how to get to and modify config files on Asus routers? (I tried googling but haven't found anything specifically useful yet :( )
 

RMerlin

Asuswrt-Merlin dev
You need a custom firmware to customize config files, and there isn't one available for the GT-AC5300.

I only posted the config file as an example of the type of parameters handled by the mcpd daemon.
 

organshifter

Regular Contributor
Not sure if this is the setting you're looking for or not, but following "Wireless>Professional (Tab)" on my GT-AX11000, "Enable IGMP Snooping" is an option which can be Enabled/Disabled across all three bands. If not the same thing, disregard.
 

organshifter

Regular Contributor
@organshifter thanks for checking your GT-AX11000 to make sure at least the IGMP Snooping function is available, in case I need to upgrade to that in the future.
Welcome. The GT-AC5300 has that setting as well. Being that it's disabled by default, maybe you didn't enable it? Definitely worth having a look.
 

Smallnetbuilderguy

New Around Here
Yes I can confirm that on my GT-AC5300, IGMP Snooping is only available in Wireless > Professional Tab too, not in LAN > IPTV.

It looks like Asus has standardized this change across their new routers including the AX series, due to a "new daemon" that I am not familiar with.

I have no idea if this new daemon means better or worse for IPTV applications. It does seem owners of newer routers have issues with IPTV on these newer Asus routers and eventually had to resort to getting a Netgear or Ubiquiti network switch with IGMP Snooping built-in.
 

demerx

New Around Here
Hi All,

Anyone know how to use Routed IPTV (KPN/ XS4ALL) with a Asus AX router? Internet is VLAN 6/ IPTV VLAN 4. My current AC87U is supporting this but on newer AX92U VLAN and IGMP Proxy at same moment is nog possible.

Perhaps anyone knows how and with which router this is possible.

Thank you all
 

xanman

New Around Here
This is my /var/mcpd.conf

[email protected]:/tmp/home/root# cat /var/mcpd.conf
##### IGMP configuration #####
igmp-default-version 2
igmp-query-interval 20
igmp-query-response-interval 100
igmp-last-member-query-interval 10
igmp-robustness-value 2
igmp-max-groups 25
igmp-max-sources 25
igmp-max-members 25
igmp-fast-leave 1
igmp-admission-required 0
igmp-admission-bridging-filter 0
igmp-proxy-interfaces eth0
igmp-snooping-interfaces br0
igmp-mcast-interfaces eth0
#
#Begin MLD configuration
#
mld-default-version 2
mld-query-interval 125
mld-query-response-interval 10
mld-last-member-query-interval 10
mld-robustness-value 2
mld-max-groups 10
mld-max-sources 10
mld-max-members 10
mld-fast-leave 1
mld-admission-required 0
mld-admission-bridging-filter 0
mld-proxy-enable 1
mld-snooping-enable 1
mld-proxy-interfaces eth0
mld-snooping-interfaces br0
mld-mcast-interfaces eth0
#
#End MLD configuration
#
##### MCAST configuration #####
igmp-mcast-snoop-exceptions 239.255.255.250/255.255.255.255 224.0.255.135/255.25 5.255.255
mld-mcast-snoop-exceptions ff05::0001:0003/ffff:ffff:ffff:ffff:ffff:ffff:ffff:ff ff

The one difference I noticed is that the igmp-query-interval is 20. How would I change it to 40?
 

ColinTaylor

Part of the Furniture
The one difference I noticed is that the igmp-query-interval is 20.
Different from what? The only other reference to igmp-query-interval in this thread is post #2 where it is also set to 20.
 

ColinTaylor

Part of the Furniture
Check the image in post #6
Thanks, I see it now. It looks like all of those values are different to some extent, not just that one.

If you need to change any of the values you'll need to use a postconf script (/jffs/scripts/mcpd.postconf).
 

xanman

New Around Here
Thanks, I see it now. It looks like all of those values are different to some extent, not just that one.

If you need to change any of the values you'll need to use a postconf script (/jffs/scripts/mcpd.postconf).
Thank you,

So I create a file called "mcpd.postconf"

add

Code:
pc_replace "igmp-query-interval 20" "igmp-query-interval 40"
pc_replace "igmp-query-response-interval 100 " "igmp-query-response-interval 10"
pc_replace "igmp-robustness-value 2" "igmp-robustness-value 4"
pc_replace "igmp-max-groups 25" "igmp-max-groups 16"
pc_replace "igmp-max-sources 25" "igmp-max-sources 128"
pc_replace "igmp-max-members 25" "igmp-max-members 128"

and uploade it to /jffs/scripts/mcpd.postconf

I am just struggling to find the command to upload it.
 

ColinTaylor

Part of the Furniture
Not quite:
Code:
#!/bin/sh
CONFIG=$1
source /usr/sbin/helper.sh

pc_replace "igmp-query-interval 20" "igmp-query-interval 40" $CONFIG
pc_replace "igmp-query-response-interval 100 " "igmp-query-response-interval 10" $CONFIG
pc_replace "igmp-robustness-value 2" "igmp-robustness-value 4" $CONFIG
pc_replace "igmp-max-groups 25" "igmp-max-groups 16" $CONFIG
pc_replace "igmp-max-sources 25" "igmp-max-sources 128" $CONFIG
pc_replace "igmp-max-members 25" "igmp-max-members 128" $CONFIG
 

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